Fosamprenavir (Calcium Salt)

Fosamprenavir Calcium Salt (GW433908G) is an orally active inhibitor targeting HIV-1 protease and is a prodrug of Amprenavir (HY-17430). Fosamprenavir Calcium Salt is hydrolyzed into Amprenavir (VX-478) by cell phosphatases in the intestinal epithelium. Amprenavir binds to the active site of HIV-1 protease, preventing the processing of viral gag and gag-pol polyprotein precursors, thereby inhibiting the formation of mature infectious virus particles and exerting anti-HIV-1 infection activity. Fosamprenavir Calcium Salt can be used for the study of human immunodeficiency virus (HIV-1) infection^[1][2]. In Vitro:Amprenavir, the active form of Fosamprenavir Calcium Salt (GW433908G), can bind to and inhibit the activity of pepsin in vitro with an IC₅₀ of 3.56 μM^[2].
In Vivo:Fosamprenavir (20 mg/kg/day; gavage; daily; 4 weeks) Calcium Salt (GW433908G) protects against pepsin-mediated laryngeal injury (e.g., reactive epithelium, increased intraepithelial inflammatory cells, and apoptosis) in the Jackson A/J mouse model of laryngeal reflux^[2].